Analysis antibiotic, meat

A critical study of reference standards for residue analysis of chloramphenicol in meat and milk was also carried out using a radioimmunoassay and gas chromatography (GC) equipped with electron capture and mass detectors (41). Although the concentration of chloramphenicol was only 1 ppb in milk and 10 ppb in meat, approximately 70% of the antibiotic could be recovered by the assay. A stability study of chloramphenicol in milk samples stored at 30 to 80 C showed that stability decreases with increasing drug concentration when the sample is stored at 30 C. 

DG Kennedy, RJ McCracken, A Cannavan, SA Kewitt. Use of liquid chromatography-mass spectrometry in the analysis of residue antibiotics in meat and milk. J Chromatogr 812 77-98, 1998. 

Another current trend that is well underway is the use of more specific analytical instrumentation that allows less extensive sample preparation. The development of mass spectrometric techniques, particularly tandem MS linked to a HPLC or flow injection system, has allowed the specific and sensitive analysis of simple extracts of biological samples (68,70-72). A similar HPLC with UV detection would require significantly more extensive sample preparation effort and, importantly, more method development time. Currently, the bulk of the HPLC-MS efforts have been applied to the analysis of drugs and metabolites in biological samples. Kristiansen et al. (73) have also applied flow-injection tandem mass spectrometry to measure sulfonamide antibiotics in meat and blood using a very simple ethyl acetate extraction step. This important technique will surely find many more applications in the future. 

Okerman et al. compared the performance of a Tetrasensor with three microbial inhibition assays for the analysis of tetracycline antibiotics in tissue. The group concluded that when large numbers of samples have to be analyzed without the requirement for immediate results, classical agar diffusion tests with thin plates and performed as prescribed for the EPT still seem the most economical choice. However, the receptor-based test Tetrasensor was recommended for use in official surveys and also in cases when immediate results are required. Unlike the inhibition tests, this receptor test does not require a well-equipped laboratory for use and is more suited for the meat industry. ... 

LC-MS finds wide application in the analysis of compounds that are not amenable to GC-MS, i.e. compounds that are highly polar, ionic and thermo-labile, as well as (bio)macromolecules. In environmental applications, LC-MS is applied, often in combination with off-line or on-line solid-phase extraction, to identify pesticides, herbicides, surfactants and other environmental contaminants. LC-MS plays a role in the confirmation of the presence of antibiotic residues in meat, milk and other food products. Furthermore, there is a substantial role for LC-MS in the detection and identification of new compounds in extracts from natural products and the process control of fermentation broths for industrial production of such compounds, e.g. for medicinal use. LC-MS technology is also widely applied in the characterization of peptides and proteins, e.g. rapid molecular-mass determination, peptide mapping, peptide sequencing and the study of protein conformation and noncovalent interactions of drugs, peptides and other compounds with proteins and DNA. However, the most important application area... 

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